1. wo charges of 15 pC and –40 pC are inside a cube with sides that are of 0.40-m length. Determine the net electric flux through the surface of the cube.
a) +2.8 N ⋅m2/C
b) –1.1 N ⋅m2/C
c) +1.1 N ⋅m2/C
d) –2.8 N ⋅m2/C
e) –0.47 N ⋅m2/C

2. A closed surface, in the shape of a cube of side a, is oriented as shown above in a region where there is a constant electric field of magnitude E parallel to the x-axis. The total electric flux through the cubical surface is:
a. -Ea2
b. zero
c. Ea2
d. 2 Ea2
e. 6 Ea2

3. What is the net charge shown in this figure?
C) C
D) times the charge of an electron